This proposal seeks four years of funding to develop Dr. Helen Wu's independent research career in the field of drug addiction within vulnerable populations through a NIDA Mentored Research Scientist Development Award (K01). This K01 will provide additional training that is designed to integrate addiction theory, the social etiology of substance abuse and dependence, and advanced interview methodology and statistical methods. The applicant's strong academic background and research training provide an excellent foundation on which to build new skills and carry out the proposed research plan. The specific training goals are to: 1) gain a solid foundation in the clinical assessment of addiction;2) increase the understanding of how stress influences drug use;3) strengthen the candidate's methodological and statistical skills;4) implement a longitudinal study to examine the influence of stressors on substance use among young, low-income women;5) develop a grant proposal (R01) to study the impact of stress on the trajectory of the progression of drug use to abuse and/or dependence;and 6) foster training in the responsible conduct of research. Dr. Wu's career development plan includes supervised study with Linda Cottier, Ph.D., on epidemiological and substance abuse issues;with Abbey Berenson, M.D., on clinical research and general career development;with James Grady, Dr. P.H., on advanced statistical methods;and with Jay Turner, Ph.D., on stress measurement in addiction research. These experts constitute a strong, multidisciplinary mentoring team that will be fundamental to Dr. Wu's career development during the award period. The reason the Candidate is seeking a K01 to remain at UTMB is because she must have access to a readily-available gynecological patient population from the Regional Maternal and Child Health Program (RMCHP) in Texas to carry out the research plan. Specifically, this study aims to examine 1) whether the overall stress burden will predict more problem drug use;2) whether there is a threshold effect of stress on problem drug use;and 3) whether certain at-risk subgroups are more susceptible to using drugs when exposed to stress. To accomplish these aims, the candidate will recruit 300 low-income women, 18-25 years of age, who seek care at the RMCHP clinics. She will conduct face-to-face interviews at baseline, 6 and 12 months and an 8-day daily diary telephone interviews of stressors and drug use and related symptoms. This research will contribute to identifying and treating stress-related substance abuse in this vulnerable population. Relevance: The project is innovative because it aims to improve methods of identification and intervention for stress-related substance use in a non-addiction-treatment clinical setting of gynecological care clinics. These clinics provide an ideal setting for substance use prevention and intervention, because many poor women only receive care from obstetricians and gynecologists through the life cycle.